The aim of this project is to remove all cellular material from dog carotid arteries by a procedure employing detergents and DNA'se and arrive at a preparation consisting of extra cellular biomatrix. This material is bounded on the luminal side by a continuous sheet of basement membrane, the natural substratum of endothelial cells. The physical properties of the "acellular arteries" are similar to those of the intact vessel. In addition they may be dried and rehydrated and sterilized without changes of their physical properties. Sterile acellular arteries will be surgically reimplanted into the carotid position of dogs and evaluated as to their suitability as small arterial prosthesis. Survival of the graft overtime and it's interaction with blood materials, recellularization and formation of organized tissue on the antiluminal surface will be investigated. The need for crosslinking the graft material as well as surface modifications with fibro nectin will also be part of our investigation. Extensive preliminary experimenttion has shown 80% of the implanted grafts to survive essentially unchanged, and patent to blood flow for 90 days. Extensive recellularization takes place with cells which resemble native endothelium. Characterization of these cells is also part of this project.